Poison maidens and others

In a gothic story "Rappaccini's Daughter" by Nathaniel Hawthorne, there is a young woman made of poison, immune to it and can become deadly. Beatrice, daughter of a botanist raised in her father's incredible garden of freakishly weird experimental plants, and exotic poisonous flowers. This made her immune to their poison, so when a man touched her, his skin turned purple and sore. 

This is very similar to the Vishakanya, poison flower women from Sanskrit mythology. These women were poison to anyone else, after feeding on small amounts of poisons from a very young age. This made them physically toxic, and anyone in close contact with them perished. They were used as assassins and seductresses to kill enemies. The story about these poison maidens comes from the time of Chandragupta Maurya (c. 320-298 BCE) the first emperor of the Maurya Empire in India.

Could all of this be so far fetched? 

There was Mithridates VI Eupator (134 - 64 BCE), king of Pontus in Anatolia. He was crowned at the age of 14, An enemy of Rome, was nicknamed "The Poison King" who ate toxins to build an immunity, often small amounts of diluted poisonous plants. He was a mad king, who fought in wars against Rome,  and he was responsible for the massacre of 80,000 Roman citizens. He wanted to increase his Black Sea empire. He had multiple wives, dozens of mistresses and many opffspring. All of them suffered a dreadful fate after the king committed suicide.

Because of this king, the scientific term "Mithridatism" applies to those taking poisons to get immunity, in slow small amounts, such as people living in the Andes who can tolerate certain poisons. For them it's a genetic immunity for higher land environment arsenic levels in the water there. 

Some have exposed themselves to snake venom, to make themselves resistant and survive bites that would ve dangerous to everyone else.

The truth is humans can't be immune to poisons but some could build up a tolerance and resistance to poison. It also doesn't make these people poisonous to others, but they might carry antibodies to the next person.  

Storm Valkyrie ☠️